No it's not the case unless Russia, Serbia, Bielorrusia, Ukraine, Hungary, Slovenia, Moldova, etc... are not white countries by your standards.
For the fucked up EU countries the reasons are an aging population, a younger generation that doesn't want the shitty jobs, that can't commit to a lasting relationship and can't afford to have kids because the fiat money system is broken and also because it's simply more profitable to employ immigrants.
